title: Risk factors for intraprocedural and clinically significant delayed bleeding after wide-field endoscopic mucosal resection of large colonic lesions.
abstract: OBJECTIVE
  Wide-field endoscopic mucosal resection (WF-EMR) of large sessile colonic polyps is a safe and cost-effective outpatient treatment. Bleeding is the main complication. Few studies have examined risk factors for bleeding during the procedure (intraprocedural bleeding [IPB]) or after it (clinically significant post-endoscopic bleeding [CSPEB]). We investigated factors associated with IPB and CSPEB in a large prospective study.
  
  
  METHODS
  We analyzed data from WF-EMRs of sessile colorectal polyps ≥ 20 mm in size (mean size, 35.5 mm), which were performed on 1172 patients (mean age, 67.8 years) from June 2008-March 2013 at 7 tertiary hospitals as part of the Australian Colonic Endoscopic Resection Study. Data were collected on characteristics of patients and lesions, along with outcomes of procedures and clinical and histologic analyses. Independent predictors of IPB and CSPEB were identified by multiple logistic regression analysis.
  
  
  RESULTS
  Of the patients studied, 133 (11.3%) had IPB. Independent predictors included increasing lesion size (odds ratio, 1.24/10 mm; P < .001), Paris endoscopic classification of 0-IIa + Is (odds ratio, 2.12; P = .004), tubulovillous or villous histology (odds ratio, 1.84; P = .007), and study institutions that performed the procedure on fewer than 75 patients (odds ratio, 3.78; P < .001). All IPB was successfully controlled endoscopically. IPB prolonged procedures and was associated with early recurrence (relative risk, 1.68; P = .011). Seventy-three patients (6.2%) had CSPEB. On multivariable analysis, CSPEB was associated with proximal colon location (odds ratio, 3.72; P < .001), use of an electrosurgical current not controlled by a microprocessor (odds ratio, 2.03; P = .038), and IPB (odds ratio, 2.16; P = .016). Lesion size and comorbidities did not predict CSPEB.
  
  
  CONCLUSIONS
  In a prospective study of patients undergoing WF-EMR of large sessile colonic polyps, IPB is associated with larger lesions, lesion histology, and Paris endoscopic classification of type 0-IIa + Is. IPB prolongs the duration of the procedure, is a marker for recurrence, and is associated with CSPEB. CSPEB occurs most frequently in the proximal colon and less when current is controlled by a microprocessor.
authors.affiliation: Department of Gastroenterology and Hepatology, University of Sydney at Westmead Hospital, Sydney, NSW, Australia.
authors.forename: Nicholas G
authors.initials: NG
authors.lastname: Burgess
authors.affiliation: Department of Gastroenterology and Hepatology, University of Sydney at Westmead Hospital, Sydney, NSW, Australia.
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Metz
authors.affiliation: Department of Gastroenterology and Hepatology, University of Sydney at Westmead Hospital, Sydney, NSW, Australia.
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Williams
authors.affiliation: Department of Gastroenterology and Hepatology, Lyell McEwin Hospital, Adelaide, SA, Australia.
authors.forename: Rajvinder
authors.initials: R
authors.lastname: Singh
authors.affiliation: Department of Gastroenterology and Hepatology, Lyell McEwin Hospital, Adelaide, SA, Australia.
authors.forename: William
authors.initials: W
authors.lastname: Tam
authors.affiliation: Department of Gastroenterology and Hepatology, Princess Alexandra Hospital, Brisbane, QLD, Australia; Department of Gastroenterology and Hepatology, Greenslopes Private Hospital, Brisbane, QLD, Australia.
authors.forename: Luke F
authors.initials: LF
authors.lastname: Hourigan
authors.affiliation: Department of Gastroenterology and Hepatology, The Alfred Hospital, Melbourne, VIC, Australia; Department of Gastroenterology and Hepatology, Western Hospital, Melbourne, VIC, Australia.
authors.forename: Simon A
authors.initials: SA
authors.lastname: Zanati
authors.affiliation: Department of Gastroenterology and Hepatology, The Alfred Hospital, Melbourne, VIC, Australia; Department of Gastroenterology and Hepatology, Epworth Hospital, Melbourne VIC, Australia.
authors.forename: Gregor J
authors.initials: GJ
authors.lastname: Brown
authors.affiliation: Department of Gastroenterology and Hepatology, University of Sydney at Westmead Hospital, Sydney, NSW, Australia.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Sonson
authors.affiliation: Department of Gastroenterology and Hepatology, University of Sydney at Westmead Hospital, Sydney, NSW, Australia. Electronic address: michael@citywestgastro.com.au.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Bourke
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001315:Australia / Q000453:epidemiology; D003110:Colonic Neoplasms / Q000473:pathology* / Q000601:surgery*; D003111:Colonic Polyps / Q000473:pathology* / Q000601:surgery*; D004724:Endoscopy / Q000009:adverse effects*; D005260:Female; D006471:Gastrointestinal Hemorrhage / Q000453:epidemiology*; D006651:Histocytochemistry; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors
keywords: ACE Study; Colonoscopy; Colorectal Neoplasms; Hemorrhage; Polypectomy